The invention relates generally to fluid conduit fittings or coupling devices. More particularly, the invention relates to fluid conduit fittings or couplings adapted for quickly and conveniently connecting or disconnecting a pair of fluid conduits.
A wide variety of fluid conduit fittings and couplings have been provided in the prior art for connecting fluid conduits in fluid communication with one another. One type of such previously-known couplings includes an external, generally U-shaped staple or spring clip inserted into lateral openings in an assembled fitting or coupling for purposes of interlocking the components of the assembly to one another. Frequently, however, such staples or clips become misplaced, or become permanently damaged or deformed due to repeated assembly and disassembly of the coupling, and thus must be replaced. In addition, such staples or clips frequently protrude outwardly from the fitting or coupling to an extent where they can easily snag on, or interfere with, other adjacent components or devices. Additionally, especially in high pressure applications, such staples or clips frequently must be quite stiff and relatively bulky this making them difficult or cumbersome to install or remove from a fluid coupling or fitting.
Other prior art fittings or couplings require external clamps or rings for compressing a flexible fluid conduit onto a nipple-like structure. Such compression fittings are frequently very time-consuming to install or remove during connection or disconnection of the fluid conduit. Like the staples and clips described above, external clamps or rings often become misplaced or permanently deformed or damaged during assembly and disassembly of the fluid conduit fitting and therefore must frequently be replaced.
Still other well-known fitting or coupling assemblies include male and female coupling elements that are threadably connectable to one another. Such threaded couplings, which typically rely upon the threaded engagement of the coupling elements both for mechanical interconnection and for fluid sealing, are frequently susceptible to leakage, thereby requiring application of sealing compounds or tape-like sealants to the threads each time the coupling elements are connected to one another. In addition, these fitting or coupling assemblies, like those discussed above, typically do not provide for fluid pressure relief prior to complete disconnection of the fluid conduits.
Accordingly, it is one of the objects of the present invention to provide an improved fitting or coupling assembly especially adapted for quickly, conveniently, and releasably connecting a pair of fluid conduits.
Another object of the present invention is to provide a fitting or coupling assembly that can be conveniently and easily disconnected in order to separate the fluid conduits from one another.
A further object of the present invention is to provide a fluid conduit fitting or coupling assembly that is relatively simple and inexpensive to manufacture and use, that is durable and reliable, and that provides a strong interlocking connection between the fluid conduits being joined together.
Still another object of the present invention is to provide a feature in an improved fitting or coupling assembly that substantially prevents complete disconnection of the fluid conduits until any internal fluid pressure (positive or negative) is relieved to a predetermined level (generally atmospheric pressure).
According to the general invention, a quick-connect fitting assembly for releasably connecting a pair of fluid conduits in fluid communication with one another includes a socket on one of the fluid conduits for receiving the other fluid conduit inserted longitudinally inwardly into the socket. The inserted fluid conduit has a generally laterally-extending protuberance thereon, and a retaining assembly within, or adjacent to, the fluid socket includes at least one resilient spring or barb member that is longitudinally and interlockingly engageable with the protuberance on the inserted fluid conduit. Preferably, a number of such barb members each include an anchoring portion that is longitudinally restrained by a retaining member, and a barb portion that is resiliently deflectable during insertion of the inserted fluid conduit. Once the spring or barb member is interlocked with the inserted fluid conduit, the resilient barb portion resists removal of the inserted fluid conduit until the retaining apparatus is disassembled.
The spring or barb members are preferably anchored and restrained by a retaining ring, and a pair of longitudinally interconnectable collar members serve to longitudinally interconnect and restrain the retaining ring and barb members within the fitting assembly. In one of the preferred embodiments, a first of the collar members is longitudinally engageable with an outwardly-protruding flange on the socket, and is threadably interconnectable with a second collar member on the inserted fluid conduit. In such an arrangement the second collar member includes an internal shoulder and recessed portion for receiving and longitudinally restraining at least the retaining ring and preferably the anchoring portions of the barb members. The preferred retaining ring of this embodiment includes a number of generally arcuate retaining ring segments or sections interconnected by retaining ring pins, to which generally hook-shaped ends of the anchoring portions of the barb members are connected.
The above-discussed embodiments of a quick-connect fitting assembly according to the present invention can also include a feature for relieving the internal fluid pressure of a charge fluid conduit during the initial stages of disconnection of the fluid conduits. In one such arrangement, the length, thread type, and thread helix of the various fitting components can be chosen such that pressure relief brings to occur after a preselected number of unthreading turns of these components relative to one another. An additional number of turns are required to completely disconnect the fluid conduits, thereby allowing for complete pressure relief prior to complete disconnection.
In another of the preferred embodiments of the present invention, the threaded collar members discussed above are replaced by relatively rotatable collar members having an interlocking, "bayonet-type" mutual engagement, in which one or more grooves or slots on one collar member are adapted to interlockingly and releasably receive and restrain one or more pins on the other collar member in order to interconnect the collar members and to longitudinally restrain the fluid conduits and the retaining assembly discussed above. In this arrangement, the grooves or slots can be configured to provide a feature by which complete disconnection of the fluid conduits is substantially prevented until any fluid pressure in the conduits is sufficiently relieved. After the pressure is relieved, the collar members can then be disengaged to allow complete disconnection of the fluid conduits.
In addition to the above, the various preferred embodiments of a fluid fitting or conduit assembly according to the present invention can include one or more sealing members on the inner and/or outer longitudinal sides of the retaining structure in order to substantially prevent fluid leakage from the joined conduits. Additionally, a lateral supporting ring is preferably disposed within the retaining structure to provide lateral support for the inserted fluid conduit within the socket, with the lateral support ring being either a separate member or integrally formed with the above-mentioned retaining ring. The lateral supporting ring can also serve as a retaining structure for the above-mentioned sealing member or members.
Additional objects, advantages and features of the present invention will become apparent from the following description and the appended claims, taken in conjunction with the accompanying drawings.